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Synthesis and characterisation of FeTiO3 perovskite nanomaterials for electrochemical energy storage application
No full textIn this study, ilmenite iron titanate (FeTiO3)] perovskite nanoparticles were synthesised by wet chemical method and sintered at two temperatures, namely 350 degrees C (FT350) and 500 degrees C (FT500). The phase structure, crystallinity, microstructure, particle size, and purity of the sintered samples were extensively studied. Electrochemical measurements such as cyclic voltammetric studies, electrochemical impedance spectroscopy (EIS), and discharge measurements were carried out. The results of the cyclic voltammetric studies showed that sample prepared at 500 degrees C delivers high specific capacitance (42 F g(-1)), which is significantly greater as compared to that of 350 degrees C sample. Moreover, the results of the EIS study show that 500 degrees C delivers better capacitance than 350 degrees C. The FeTiO3 samples sintered at 350 and 500 degrees C used as cathodes in a novel Mg/FeTiO3 cell delivered a discharge capacity of 129 and 90 mA h g(-1), respectively. According to the study's data, for the first time it has confirmed that FeTiO3 is suitable for using it as a cathode material in Mg/FeTiO3 primary cell. The discharge capacity of 500 degrees C was found to be 70% higher when compared to 350 degrees C. Thus, the proposed results show that the electrochemical behaviour of the sintered sample 500 degrees C is superior to that of 350 degrees C
The fatal flaws of compassionate conservation
No full textArticle impact statement: Wallach et al.'s framing of compassionate conservation is flawed and impractical and could be dangerous for people, wildlife, and ecosystems
NHC-Catalyzed 3+3] Annulation of Thioamides and Modified Enals for the Enantioselective Synthesis of Functionalized Thiazinones
No full textN-Heterocyclic carbene (NHC)-catalyzed 3 + 3] annulation of thioamides with modified enals allowing the enantioselective synthesis of functionalized 1,3-thiazin-4-ones is reported. The NHC generated from the chiral triazolium salt was optimal and the reaction is initiated by the thia-Michael addition to catalytically generated alpha,beta-unsaturated acylazolium intermediates derived from 2-bromoenals, followed by intramolecular cyclization. This operationally simple procedure offers a straightforward and rapid access to target compounds in moderate to good yields and enantiomeric ratio values
Low Power, CMOS-MoS2 Memtransistor based Neuromorphic Hybrid Architecture for Wake-Up Systems
No full textNeuromorphic architectures have become essential building blocks for next-generation computational systems, where intelligence is embedded directly onto low power, small area, and computationally efficient hardware devices. In such devices, realization of neural algorithms requires storage of weights in digital memories, which is a bottleneck in terms of power and area. We hereby propose a biologically inspired low power, hybrid architectural framework for wake-up systems. This architecture utilizes our novel high-performance, ultra-low power molybdenum disulphide (MoS2) based two-dimensional synaptic memtransistor as an analogue memory. Furthermore, it exploits random device mismatches to implement the population coding scheme. Power consumption per CMOS neuron block was found to be 3 nw in the 65 nm process technology, while the energy consumption per cycle was 0.3 pJ for potentiation and 20 pJ for depression cycles of the synaptic device. The proposed framework was demonstrated for classification and regression tasks, using both off-chip and simplified on-chip sign-based learning techniques
Synthesis, structural, thermal, mechanical, laser damage threshold and DFT investigations on bis (2-methylimidazolium-4-aminobenzoate) single crystal
No full textAn organic salt, bis (2-methylimidazolium-4-aminobenzoate) (MIAB) was synthesized and single crystals grown successfully by slow solvent evaporation solution growth technique using ethyl acetate as solvent at room temperature. Fourier transform infrared (FTIR) spectral analysis was carried out to detect the presence of functional groups in the MIAB salt crystal. H-1 and C-13 spectra were recorded to confirm the presence of various kinds of proton and carbon environments thereby establish the molecular structure of MIAB crystal. Single crystal X-ray diffraction analysis (SCXRD) reveal that the crystal belongs to monoclinic system centrosymmetric space group, P2(1/)c. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) confirms that the MIAB crystal is thermally stable up to 250 degrees C. The mechanical properties of the grown crystal were determined by Vickers Microhardness test. Computational studies were performed using Gaussian 09 software by 6.31 g basis set level. The calculated first order hyperpolarizability (beta) of MIAB from computational studies is 5.01 times that of Potassium dihydrogen phosphate (KDP). The laser damage threshold value of the MIAB is found to be 1.44 GW/cm(2). Z-scan technique reveals the optical non-linearity of the crystal
Nucleolus: A Protein Quality Control Compartment
No full textFrottin et al. uncovered a role for the nucleolus as a key quality control compartment that regulates misfolded nuclear proteins. This nonmembrane compartment achieves this by forming liquid-like protein condensates that aid protein refolding in a heat-shock protein (Hsp)70-dependent manner. This liquid-liquid phase separation (LLPS)-mediated nuclear quality control mechanism is perturbed during neurodegeneration
Self-assembled Pd3L2 cages having flexible tri-imidazole donors
No full textFour new M3L2 molecular cages (CA1-CA4) have been synthesized in excellent yield via coordination driven self -assembly of flexible tri-imidazole donors based on triazine (L1) and tri-phenyl benzene (L2) core with 90 degrees cis-blocked metal acceptors of Pd(II). Two of them CA1 and CA2 are highly soluble in water. All the cages were characterized by spectroscopic studies and ESI-MS; CA3 and CA4 also by X-ray diffraction. Selective formation of two separate cages CA3 and CA4 was noticed instead of a hetero-ligand cage, when the metal acceptor (dppf)Pd(OTf)(2) was treated with a mixture of ligands L1 and L2
Iduronate-2-Sulfatase-Regulated Dermatan Sulfate Levels Potentiate the Invasion of Breast Cancer Epithelia through Collagen Matrix
No full textCancer epithelia show elevation in levels of sulfated proteoglycans including dermatan sulfates (DS). The effect of increased DS on cancer cell behavior is still unclear. We hypothesized that decreased expression of the enzyme Iduronate-2-sulfatase (IDS) can lead to increased DS levels, which would enhance the invasion of cancer cells. Breast cancer sections shows depleted IDS levels in tumor epithelia, when compared with adjacent untransformed breast tissues. IDS signals showed a progressive decrease in the non-transformed HMLE, transformed but non-invasive MCF-7 and transformed and invasive MDA-MB-231 cells, respectively, when cultured on Type 1 collagen scaffolds. DS levels measured by ELISA increased in an inverse-association with IDS levels. Knockdown of IDS in MCF-7 epithelia also increased the levels of DS. MCF-7 cells with depleted IDS expression, when imaged using two photon-excited fluorescence and second harmonic generation microscopy, exhibited a mesenchymal morphology with multiple cytoplasmic projections compared with epithelioid control cells, interacted with their surrounding matrix, and showed increased invasion through Type 1 collagen matrices. Both these traits were phenocopied when control MCF-7 cells were cultivated on Type 1 collagen gels polymerized in the presence of DS. In monolayer cultures, DS had no effect on MCF-7 migration. In the context of our demonstration that DS enhances the elastic modulus of Type 1 collagen gels, we propose that a decrease of IDS expression leads to accumulation within cancer epithelia of DS: the latter remodels the collagen around cancer cells leading to changes in cell shape and invasiveness through fibrillar matrix milieu
Performance of Composite Insulators Used for Electric Transmission under Extreme Climatic Conditions
No full textComposite or polymeric insulators are being used in various parts of the world for high-voltage transmission and distribution lines. In some parts of India, places in the states like Rajasthan and Gujarat experience an increase in the daytime temperature up to 50 degrees C, while the nighttime temperature reduces as low as 3-5 degrees C. Because of these extreme temperature variations along with electric stress and humidity conditions, composite insulators have to perform well over their lifetime to ensure the reliability of the transmission network. In the present work, experimental conditions are simulated with temperature variation from 50 to 3-5 degrees C along with electrical stress, humidity variation, pollution, and ultraviolet radiations. Accelerated aging studies with these stresses are conducted to understand the degradation on the insulator similar to the field conditions. Surface resistivity measurements, leakage current analysis, and surface degradation studies using thermogravimetric analysis, scanning electron microscopy, energy-dispersive x-ray, and Fourier transform infrared spectroscopy (FTIR) are conducted. Some interesting results obtained from the study are presented. Experimentation under extreme conditions with polluted insulators showed considerable degradation which was inferred from the material testing analysis. The insulator slabs on which electrical stress was not applied showed a considerable peak at 1500 cm(-1) in the FTIR spectra, indicating the generation of low molecular weight PDMS chains from the bulk due to UV aging and thermal stress, while the degradation pattern of non-polluted sample was severe compared to the slab treated but was considerably less severe in comparison with the polluted insulator sample exhibiting pollution can considerably increase degradation rate
Measurement of the top quark polarization and t(t)over-barspin correlations using dilepton final states in proton-proton collisions at root s=13 TeV
No full textMeasurements of the top quark polarization and top quark pair (t (t) over bar) spin correlations are presented using events containing two oppositely charged leptons (e(+)e(-), e(+/-)mu(-/+), or mu(+)mu(-)) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb(-1) . A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the t (t) over bar production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to -0.24 < C-tG/Lambda(2) < 0.07 TeV-2 and -0.33 < C-tG(I)/Lambda(2) < 0.20 TeV-2, respectively, at the 95% confidence level